During adolescence health habits that persist into adulthood are being established. While it is important that a wide range of health risks be addressed in well visits, most clinicians lack IT systems that efficiently screen teens for health risks and support evidence-based motivational counseling. After the health visits clinicians are not able to offer supports to transform motivation to change a health behavior into better outcomes for adolescents. Appropriate community IT venues to use to support change in this generation of "digitally native" teens are the widely used cell phone text messaging and Internet based social networking sites. To meet these needs the Healthy Teens TXT ME project will develop and pilot test a new model of IT supported teen health counseling and post visit supports in rural primary care settings. The two health risks that will be studied are tobacco use and inadequate exercise. The full model will utilize IT in each of the following ways: 1) Consistent primary care screening of health risks and assessment of patient motivation utilizing PDA (personal digital assistant) technology;2) Clinical counseling tailored to risks and motivational factors supported by PDA technology;and 3) Post-visit supports to transform teen intentions into actions changing health behaviors by strengthening teen commitment and self efficacy for their goals via cell phone text messaging, and increasing social support and access to resources via Internet social network sites. The specific aims of this R21 project to prepare for a large scale investigation of this approach are to: 1) Enhance the Healthy Teens PDA (personal data assistant)-based health risk screening tool with clinician prompts to support effective counseling for exercise and tobacco cessation from evidence based literature and existing public health and patient counseling programs. 2) Develop the format, message delivery algorithm and technological processes to link PDA-based teen health screening data from the primary care visit to tailored follow up health behavior change messages delivered to adolescents by cell phone text messaging to reinforce planned changes in exercise or tobacco use. 3) Develop the prototype of adolescent health behavior change support via an Internet Social Network site where adolescents will be linked to others in the project trying to change a specific health behavior (exercise or tobacco) and access web-based resources. 4) Conduct a small feasibility trial of the exercise component of the TXT ME model that will provide health risk screening using PDA technology to screen and prompt clinicians, and provide via post-visit IT reinforcement to make changes when a teen indicates interest in changing exercise. Evaluation will include short term outcomes related to message content and health behavior outcomes. This project has potential widespread impact because of the marked increase of risky health behaviors in adolescence that lead to obesity and cancer. The current clinical care system is inadequate in its screening, counseling and provision of supports for youth to implement steps to stop smoking or exercise more. The proposed community IT supports could be provided by public health, health systems, community organizations and insurers and offer a new model of preventive health care for youth.